1. Field of the Invention
The present invention relates to a device having an image sensor function and a display function, and particularly to an electronic equipment, such as an active matrix panel with a display portion made of a pixel portion including a plurality of pixel electrodes disposed in matrix, a portable terminal unit with such a display portion, or a personal computer with such a display portion, and also to a method of manufacturing the same.
2. Description of the Related Art
In recent years, a technique of a TFT using polycrystal silicon called a polysilicon TFT has been diligently investigated. As a result, it becomes possible to manufacture a driving circuit, such as a shift register, with polysilicon TFTs, and further, an active matrix type liquid crystal panel in which a pixel portion and a peripheral driving circuit for driving the pixel portion are integrated on the same substrate, has been put to practical use. Thus, the cost of the liquid crystal panel is lowered, the size thereof is reduced, the weight thereof is decreased, and the liquid crystal panel is used as a display portion of various information equipments or portable equipments, such as a personal computer, a portable telephone, a video camera, and a digital camera.
Recently, a pocket-sized small portable information processing terminal unit, which is superior in portability to a note-sized personal computer and is inexpensive, has been put to practical use, and an active matrix type liquid crystal panel is used for its display portion. In such an information processing terminal, although data can be inputted from the display portion by a touch-pen system, it is necessary to connect the terminal with a peripheral device for reading an image, such as a scanner or a digital camera, in order to input character/drawing information on a paper or picture information. For this reason, the portability of the information processing terminal is hindered. Also, an economical load for purchasing a peripheral device is imposed on a user.
An active matrix type display device is used also for a display portion of a TV meeting system, a TV telephone, a terminal for the internet, and the like. Although such a system or terminal is provided with a camera (CCD camera) for photographing an image of a dialogist or a user, a display portion and a reading portion (sensor portion) are separately manufactured and are modularized. Thus, the manufacturing cost becomes high.